Automatic testing of integrated circuits and other electronic components is performed using devices of the type illustrated, for example, in European Patent Application EP-A-0102217, which comprises a fixed supporting structure fitted with a positioning assembly in turn fitted with an electronic test head. The positioning assembly slides vertically with respect to the supporting structure, and can also be extended horizontally in an accordion-like movement along three parallel axes to position the electronic head correctly with respect to the test component or circuit carried by a manipulator. Each moving component of the positioning assembly has a lock lever mechanism, and the electronic test head is positioned manually by an operator working separately on each moving component of the positioning assembly, after releasing the corresponding lock lever mechanism. Once set to the required position, each moving component is again locked.
The above device, and others like it, have various drawbacks. In particular, positioning the electronic test head is a slow, painstaking job, by the operator having to work on a number of separate moving components and respective lock lever mechanisms. Moreover, the positioning assembly comprises a large number of moving components, and is therefore fairly complex and expensive to produce and assemble.